package com.leaf.u_jvm;

import java.lang.reflect.Field;

import sun.misc.Unsafe;


/**
 * 使用unsafe分配本机内存
 * 
 * VM Args: -Xmx20M -XX:MaxDirectMemorySize=10M
 *
 */
public class DirectMemoryOOM {

	private static final int _1MB = 1024 * 1024;
	
	public static void main(String[] args) throws Exception{
		Field unsafeField = Unsafe.class.getDeclaredFields()[0];
		unsafeField.setAccessible(true);
		Unsafe unsafe = (Unsafe) unsafeField.get(null);
		while(true){
			unsafe.allocateMemory(_1MB);
		}
	}
	
}
